python-decorators

I see patterns like def __init__(self, x, y, z): ... self.x = x self.y = y self.z = z ... quite frequently, often with a lot more parameters. Is there a good way to avoid this type of tedious repetitiveness? Should the class inherit from namedtuple instead? Edit: If you have python 3.7+ just use dataclasses A decorator solution that keeps the signature: import decorator import inspect import sys @decorator.decorator def simple_init(func, self, *args, **kws): """ @simple_init def __init__(self,a,b,...,z) dosomething() behaves like def __init__(self,a,b,...,z) self.a = a self.b = b ... self.z =

Could anyone find a problem with this @property decorator? I cannot seem to get it to assert correctly. I'm sure I'm doing some really simple thing wrong, but can anyone point my tired eyes in the right direction please? class A: def __init__(self): self.a = 0 self._b = 0 @property def b(self): return self.b @b.getter def b(self): if self._b is None: return 0 return self._b @b.setter def b(self, val): self._b = (val * 20) def test_getter_setter(): obj = A() obj.a = 1 #obj.b = 2 print obj.a, obj.b obj.b = 2 print obj.a, obj.b assert obj.b == 40 test_getter_setter() The @property decorator only

Is it possible to obtain a list of all @property decorated methods in a class? If so how? Example: class MyClass(object): @property def foo(self): pass @property def bar(self): pass How would I obtain ['foo', 'bar'] from this class? Anything decorated with property leaves a dedicated object in your class namespace. Look at the __dict__ of the class, or use the vars() function to obtain the same, and any value that is an instance of the property type is a match: [name for name, value in vars(MyClass).items() if isinstance(value, property)] Demo: >>> class MyClass(object): ... @property ... def

I'm trying to learn Decorators . I understood the concept of it and now trying to implement it. Here is the code that I've written The code is self-explanatory. It just checks whether the argument passed in int or not. def wrapper(func): def inner(): if issubclass(x,int): pass else: return 'invalid values' return inner() @wrapper def add(x,y): return x+y print add('a',2) It's throwing error saying global name 'x' is not defined . I understand that it is not defined under inner , but didnt know how to rectify this code? Where I'm going wrong? sloth Your decorator should look like: def wrapper

This question already has an answer here: How can I decorate an instance method with a decorator class? 3 answers While there are plenty of resources about using classes as decorators , I haven't been able to find any that deal with the problem of decorating methods . The goal of this question is to fix that. I will post my own solution, but of course everyone else is invited to post theirs as well. Why the "standard" implementation doesn't work The problem with the standard decorator class implementation is that python will not create a bound method of the decorated function: class Deco: def

import functools class Decor(object): def __init__(self, func): self.func = func def __call__(self, *args, **kwargs): def closure(*args, **kwargs): print args, kwargs return self.func(*args, **kwargs) return closure(*args, **kwargs) class Victim(object): @Decor def sum(self, a, b): return a+b v = Victim() v.sum(1, 2) Results in: (1, 2) {} Traceback (most recent call last): File "test.py", line 19, in <module> v.sum(1, 2) File "test.py", line 11, in __call__ return closure(*args, **kwargs) File "test.py", line 10, in closure return self.func(*args, **kwargs) TypeError: sum() takes exactly 3

Background I am running a py.test with a fixture in a conftest file . You can see the code below(this all works fine): example_test.py import pytest @pytest.fixture def platform(): return "ios" @pytest.mark.skipif("platform == 'ios'") def test_ios(platform): if platform != 'ios': raise Exception('not ios') def test_android_external(platform_external): if platform_external != 'android': raise Exception('not android') conftest.py import pytest @pytest.fixture def platform_external(): return "android" Problem Now I want to be able to skip some tests that do not apply to my current test-run. In my